An interactive account of bilingual lexical acquisition
Word acquisition starts around 6 months of age (Jusczyk and Aslin 1995; Tincoff and Jusczyk 1999; Bergelson and Swingley 2012)
Word-learning involves the (challenging) task of associating a word-form to its referential context (ambiguous, variable)
Bilinguals face the challenge of learning more than one word-form per referent
Bilinguals keep up with their monolinguals: how?
Vocabulary checklist: number/proportion of words checked by caregivers as Understands, and/or Says
| Understands | Understands & Says | |
|---|---|---|
| chair | [ ] | [ ] |
| table | [ ] | [ ] |
| … | [ ] | [ ] |
Cognate: form-similar translation equivalents (TEs)
Bilinguals acquire TEs from early ages (Bilson et al. 2015; Tsui et al. 2022)
Cognateness facilitates vocabulary growth? Mechanisms?
Lexical access is language non-selective:
Translation equivalents are co-activated, even in monolingual situations
Cognates are acquired earlier than non-cognates (Mitchell, Tsui, and Byers-Heinlein 2022; Bosch and Ramon-Casas 2014)
Dissociation between models of bilingual word processing (parallel activation) and word acquisition
:::
Word acquisition as a continuous process of lexical consolidation (Hidaka 2013; Mollica and Piantadosi 2017)
\[ \begin{aligned} \text{Age of acquisition}_{ij} &= \text{minimize}(|\text{Threshold}_{ij}-\text{Learning instances}_{ij}|) \end{aligned} \]
\[ \begin{aligned} \text{Threshold} &= 250 \\ \lambda &= 50 \end{aligned} \]
| Catalan | Spanish |
|---|---|
| 100% | 0% |
\[ \begin{aligned} \text{Learning instances}_{ij} &= Age_i \cdot Frequency_j + \\ &(Similarity_j \cdot \text{Learning instances}_{ij'}) \end{aligned} \]
| Catalan | Spanish |
|---|---|
| 60% | 40% |
| Catalan | Spanish |
|---|---|
| 75% | 25% |
On-line (formr, Arslan, Walther, and Tata 2020), inspired in MacArthur-Bates CDI (Fenson et al. 1994)
~1,600 items/words (800 Catalan + 800 Spanish)
Participants filled one of four versions of the questionnaire:
500 items: 250 Catalan + 250 Spanish
Short-listed (nouns): 302 translation equivalents (TE)
138,078 item responses from 366 participants
| 1 time | 2 times | 3 times | 4 times |
|---|---|---|---|
| 312 | 42 | 8 | 4 |
Ordinal regression model: \(P(Understands)\), \(P(Says)\)
Multilevel: Crossed-random effects
Bayesian: probability of parameter values
\[P(\text{model} | \text{data}) \propto P(\text{data} | \text{model}) \times P(\text{model})\]
| Predictor | Example |
|---|---|
| Age | Months |
| Length | Number of phonemes |
| Exposure | Lexical frequency \(\times\) Language exposure |
| Cognateness | Levenshtein similarity between a word-form and its translation |
| Two-way and three-way interactions between age, exposure, and cognateness |
| Predictor | Estimate | 95% HDI | p(H0) |
|---|---|---|---|
| Intercepts | |||
| Comprehension and Production | 0.438 | [-0.5, 0.5] | 0.088 |
| Comprehension | 0.936 | [2.44, 0.95] | 0.000 |
| Slopes | |||
| Age (+1 SD, 4.87, months) | 0.405 | [1.43, 0.45] | 0.000 |
| Exposure (+1 SD, 1.81) | 0.233 | [0.8, 0.27] | 0.000 |
| Cognateness (+1 SD, 25.65%) | 0.058 | [0.06, 0.1] | 0.037 |
| Length (+1 SD, 1.56 phonemes) | -0.062 | [-0.35, -0.04] | 0.000 |
| Age × Exposure | 0.071 | [0.16, 0.1] | 0.000 |
| Age × Cognateness | 0.014 | [0, 0.03] | 0.985 |
| Exposure × Cognateness | -0.057 | [-0.28, -0.05] | 0.000 |
| Age × Exposure × Cognateness | -0.018 | [-0.11, -0.01] | 0.975 |
Cognateness facilitates word acquisition
Only low-exposure words benefit from their cognate status: less dominant language receives more facilitation
Parallel activation as mechanism that boosts lexical consolidation: increment in cumulative learning instances
Catalan-Spanish: very specific population
Next steps: word-learning, formalisation
Levenshtein distance: number of edits for two character strings to become identical
| Orthography | Phonology | String | |
|---|---|---|---|
| Catalan | porta | /ˈpɔɾ.tə/ | pɔɾtə |
| Spanish | puerta | /ˈpweɾ.ta/ | pweɾta |
\[
1-\frac{lev(A, B)}{Max(length(A), length(B))}
\]
| Catalan | Spanish | Levenshtein |
|---|---|---|
| porta (/ˈpɔɾ.tə/) | puerta (/ˈpweɾ.ta/) | 0.50 (3) |
| taula (/ˈtaw.lə/) | mesa (/ˈmesa/) | 0.00 (5) |
| cotxe (/ˈkɔ.t͡ʃə/) | coche (/ˈkot͡ʃe/) | 0.40 (3) |
| … | … | … |
International Symposium of Psycholinguistics | Vitoria, 31st May, 2023